An electrolytic capacitor deterioration determination circuit which constitutes a ripple voltage detection circuit of an electrolytic capacitor using a capacitor for cutting direct current (DC) and an insulation transformer has been widely used. An LC tuning circuit detects a ripple voltage detection signal as a sine waveform. A rectifier circuit rectifies the sine wave detection signal. A deterioration detection unit compares a rectification signal with a reference signal.
In a power source apparatus, a ripple of an electrolytic capacitor is preferably small, and therefore, a ripple is small. If a ripple is small, it is difficult to determine deterioration of the electrolytic capacitor with high accuracy based on the ripple.
The following is a reference document.    [Document 1] Japanese Laid-open Patent Publication No. 8-248086.